Wound covering pressure relief pads

ABSTRACT

A pressure relief pad for use by persons suffering from or subject to the formation of decubitus ulcers or bedsores is described. The pressure relief pad is made from viscoelastic foam layers which provide for the redistribution of pressure around an affected or wounded area allowing the wound to heal faster. The contoured viscoelastic foam pad can be positioned over a separately applied dressing or an exudate absorbing material can be included in the pad. The contouring for the pad may be achieved by molding the foam as desired or by using a multiplicity of foam layers joined by adhesive to form the pad.

[0001] This application claims priority to provisional patentapplication No. 60/214,085, filed on Jun. 27, 2000.

BACKGROUND

[0002] The present invention relates to a pressure relief pad for use bypersons having limited mobility which may lead to the formation ofbedsores, and by persons suffering from bedsores or similar wounds whichgenerate exudates.

[0003] When a person has limited mobility or is confined to bed for anextended period of time, poor or compromised circulation can cause bloodand other bodily fluids to pool in certain areas of the body—usually atpoints or regions where a higher degree of pressure is generated betweenthe body and the surface upon which it is resting. If the pressure isnot relieved and if the fluids are not forced to move within the body,the area may become devitalized resulting in the breakdown of theintegrity of the skin and leading to decubitus ulcers or bedsores, whichmay become infected.

[0004] Some traditional ways for promoting the healing of bedsoresinclude cleansing the wound area, then covering the wound area with amoist dressing; debriding any eschar or surface necrosis, then coveringthe area with a moist dressing; or removing all devitalized tissue ifthe wound is extremely deep, covering the area with dry dressings untilthe bleeding is controlled, then covering the wound area with a moistdressing. As is known in the art, the wound area should be covered witha dressing that will keep the ulcer bed continuously moist but keep thesurrounding intact skin dry. For wounds that do not respond to the abovetreatments, the American Medical Directors Association suggestsprotecting the wound area from the adverse affects of pressure,friction, and shear. For example, the wound area can be supported on alow-air-loss mattress or on an air-fluidized bed.

SUMMARY

[0005] The present invention relates to a pressure relief pad for use bypersons suffering from or subject to the formation of decubitus ulcersor bedsores. The pressure relief pad is made from viscoelastic foamlayers which provide for the redistribution of pressure around anaffected or wounded area allowing the wound to heal faster. The pressurerelief pad can be applied, for example, over a bedsore to aid thehealing of the bedsore. The pad can also be used over an area that islikely to develop or redevelop a bedsore to redistribute the pressurearound the target area, thereby preventing bodily fluids from pooling inthat area.

[0006] In an embodiment of the pressure relief pad, a pad made fromcontoured viscoelastic foam is positioned over a separately applieddressing. In an alternative embodiment of the pressure relief pad, amultiplicity of foam layers joined by adhesive layers are used to formthe pad. In another alternative embodiment, the pad includes an exudateabsorbing material that can be placed directly against a person's openwound. In another alternative embodiment, a cavity within the pad can befilled with a gelled material to aid the wound healing process.

SUMMARY OF THE FIGURES

[0007]FIG. 1 is a perspective view of a pressure relief pad to fit overthe heel made in accordance with the present invention;

[0008]FIG. 2 is a side perspective view of the pad of FIG. 1 positionedover a patient's heel;

[0009]FIG. 3 is a bottom perspective view of the pad of FIG. 1;

[0010]FIG. 4 shows the strap protruding through the layers of the pad ofFIG. 1;

[0011]FIG. 5 is a perspective view of a first alternative embodiment ofa pressure relief pad to fit over the heel made in accordance with thepresent invention;

[0012]FIG. 6 shows the strap protruding through the shell layers andplatform layers of the pad of FIG. 5;

[0013]FIG. 7 is a cross-sectional view of the pad of FIG. 5 taken alongline 7-7;

[0014]FIG. 8 is a top perspective view of a pressure relief pad similarto the pad of FIG. 5 but designed to fit over the elbow;

[0015]FIG. 9 is a top perspective view of a pressure relief pad similarto the pad of FIG. 5 but designed to fit against the head;

[0016]FIG. 10 is a top perspective view of a pressure relief pad similarto the pad of FIG. 5 but designed to fit against the back or hip;

[0017]FIG. 11 A-D are side perspective views of the pads of FIG. 8-10positioned against a patient's elbow, head, back and hip, respectively;

[0018]FIG. 12 is a perspective view of a second alternative embodimentof a pressure relief pad made in accordance with the present inventionhaving an exudate absorbing material layer;

[0019]FIG. 13 is a side view of the pad of FIG. 12;

[0020]FIG. 14 is perspective view of a pressure relief pad to fit overthe heel made in accordance with the present invention having an exudateabsorbing material layer; and

[0021]FIG. 15 is a cross-sectional view of the pad of FIG. 14 takenalong line 15-15.

DETAILED DESCRIPTION

[0022] The present invention relates to a wound covering pressure reliefpad for use by persons suffering from or subject to the formation ofdecubitus ulcers or bedsores. The pressure relief pad is made fromviscoelastic foam layers which provide for the redistribution ofpressure around an affected or wounded area allowing the wound to healfaster. The pressure relief pad depicted in the various Figures isselected solely for the purpose of illustrating the invention. Other anddifferent wound covering pressure relief pads may utilize the inventivefeatures described herein as well.

[0023] Reference is first made to FIGS. 1-4 in which a wound coveringpressure relief pad constructed in accordance with the present inventionis generally noted by the character numeral 10. The pad 10 has acontoured shell 20, a resting platform 30 and an attachment strap 40. Asshown in FIG. 2, the pad of FIG. 1 is contoured to fit over a patient'sheel 12. However, the pad 10 may be contoured to fit over or againstother body regions, such as the elbow, head, back or hip.

[0024] Referring again to FIG. 1, the contoured shell 20 of the woundcovering pad 10 has an essentially flat base 22, having a periphery 23.A side 24, which has a predetermined thickness t₁, projects upwardlyfrom the base 22 adjacent to the periphery 23 by a predetermineddistance h₁. For the heel pad 10, the side 24 flares outward slightly toallow the patient's heel 12 and part of the foot to fit within a cavityor cup 26 formed by the base 22 and the wall 24. The cup 26 includes atop edge or rim 21 which may be continuous, or it 21 may include arecessed area 28 to allow for a better fit about the patient's heel andankle.

[0025] As shown in FIG. 3, the resting platform 30 of the wound coveringpressure relief pad 10 has an exterior shape 31 similar to the contouredshell 20, although other shapes may be used. The primary purpose of theresting platform 30 is to provide a means for dispersing the pressurecreated against the patient's skin or wound when the patient exerts adownward pressure on a particular portion of the body. In the embodimentshown, the resting platform 30 has an essentially flat bottom 32 and issolid throughout the platform 30. However, depending on the materialsselected for the platform 30, the platform 30 may have an essentiallyflat bottom 32 and be essentially hollow inside, or it 30 may have acavity similar to the contoured shell 20, or it 30 may have plugs ofmaterial removed from predetermined positions. The specific design ofthe platform 30 can be modified by the user based on how the materialdissipates pressure away from the contoured shell 20 and the expectedorientation of the patient when the pad 10 is being used.

[0026] The shell 20 and the platform 30 are each preferably made of aresilient material capable of yielding to pressure but quicklyrecovering or returning to the original state, when the pressure sourceis removed. One example of a resilient material which has thesecharacteristics is viscoelastic foam. Viscoelastic foams are availablethrough several sources, such as Dynamic Systems, Inc., 235 SunlightDrive, Leicester, N.C. 28748, which sells viscoelastic foams under thetradenames SunMate and Pudgee, and which also sells laminar cushionscomprising SunMate and Pudgee foams, and through Lendell ManufacturingInc., 5301 S. Graham Rd., St. Charles, Mich. 48655, which sellsviscoelastic foam under the product labels SRF EP-3, SRF PHS-10, SRFPHS-14 and SRF CB-11. Other foams with similar characteristics may alsobe used.

[0027] The wound covering pad 10 also optionally includes a means tosecure the shell to the heel. For example, the pad may include at leastone strap 40 to hold the pad 10 to the patient's body. As shown in FIGS.1-4, the strap 40 extends beyond the periphery 23 of the contoured shellbase 22, and is preferably positioned between the contoured shell 20 andthe resting platform 30, such that the strap 40 is not visible withinthe cavity 26. In the embodiment shown, the strap 40 is a single stripwhich runs continuously between the shell 20 and the platform 30.Alternatively, the strap 40 may be two separate pieces with a firstpiece extending from one side of the shell base and a second pieceextending from the opposite side of the shell base, or the strap may beof any form that can hold the wound covering pad 10 to the target area.Because the patient is likely to have limited mobility, the strap 40 canbe made of gauze, linen or other soft fabric strips, such as alow-denier cotton, polyester or polyester/cotton blend. However, thestrap 40 may be made of a more durable material or heavier weightmaterial, including elastic materials, if so desired by the user.

[0028] As shown in FIG. 2, the wound covering pressure relief pad 10 ispositioned on a patient's foot such that the patient's heel 12 lieswithin the cup 26, the femur 14 rests within the recession 28, and thestrap 40 can wrap around the ankle 16. When positioned on the patient,the strap 40 holds the pad 10 in position, and the viscoelastic foamshell 20 and platform 30 provide cushioning for the wound or highpressure point area. If the patient is immobile, the strap 40 may beeliminated from the pad 10. Similarly, if the pad 10 is contoured to fitover or against another body region, and the patient is not expected tomove, the strap 40 may be eliminated.

[0029] An alternative embodiment 110 of a wound covering pressurerelieving pad made in accordance with the present invention is shown inFIGS. 5-7. The wound covering pad 110 is essentially identical to thepad 10 of FIGS. 1-4 except that the shell 120 and the platform 130 areeach made of a plurality of layers 122, 132 of cushioning foam securedtogether by adhesive. Each shell or cavity-side layer 122 includes anaperture 123. Further, each shell layer 122 is essentially identicalexcept that each layer 122 is sized such that the layers 122 can bestacked to form an outwardly angled shell side 124 with a cup 126 in thecenter. The shell 120 has at least one top layer 121 that is notcontinuous, but rather is “U”-shaped. When positioned on top of theother layers 122, the top layer 121 leaves a recess 128 foraccommodating a patient's leg. Each platform or base layer 132 isessentially identical except that each base layer 132 is sized such thatthe layers 132 can be stacked to form an angled platform 130. In theembodiment shown, the platform layers 132 are solid sheets, however, thelayers 132 may include apertures if so desired by the user. Optionally,the layers of the shell 122 and of the platform 132 may be sized suchthat the sides of the shell 120 and/or the platform 132 are essentiallystraight when the layers are joined together.

[0030] The shell layers 122 and the platform layers 132 are eachpreferably made of a resilient material, such as the viscoelastic foamsSunMate, Pudgee, or SunMate/Pudgee laminar cushions manufactured byDynamic Systems, Inc. In a preferred embodiment, each layer 122, 132 hasa height h₂ of about ½″, although the heights h₂ may vary significantlyas desired by the user. Further, a layered shell 120 can be paired witha one-piece piece platform 30, or a one-piece shell 20 can be pairedwith a layered platform 130. A pressure sensitive glue, hot-meltadhesive, pressure sensitive polymer, thermoplastic film, or any otheradhesive known in the art which will bind the individual layers 122, 132together can be used to secure the shell layers 122 to each other, andto secure the platform layers 132 to each other, and to secure the shelllayers 122 to the platform layers 132. Different adhesives may be usedbetween each combination of layers, if so desired.

[0031] Similar to the pad 10, the layered pad 110 may include a strap140 for holding the pad 110 to the patient's foot. The strap 140 may bemade of gauze, linen or other soft fabric strips, but may be made of amore durable material, if desired by the user. The strap 140 may also bea single strip or composed of two or more segments, as required. In theembodiment shown, the strap 140 is a single strip of gauze positionedbetween two layers of the platform 132 so that the strap 140 is notvisible in the shell cup 126.

[0032] As shown in FIGS. 8-11D, the pads 10, 110 may be contoured to fitover or against other body regions. For example, an elbow pad 210 isshown in FIGS. 8 and 11A, a head pad 310 is shown in FIGS. 9 and 11B,and a back and hip pad 410 is shown in FIGS. 10, 11C and 11D. The sizesand shapes depicted are representative of types of pads which can bemade utilizing the inventive features herein. Other sizes and shapes maybe made as desired by the user.

[0033] An embodiment 510 of the pressure relief pad constructed inaccordance with the present invention may be used by persons sufferingfrom decubitus ulcers or similar wounds which generate exudates. Asshown in FIGS. 12 and 13, the pressure relief pad 510 includes anexudate absorbing material 512, such as a hydrophilic polyetherpolyurethane foam layer or similar absorbent material. The hydrophilicfoam layer 512 is secured to a first layer of viscoelastic foam 516 by athin layer of adhesive 514. In a preferred embodiment, the hydrophilicfoam layer 512 is slightly smaller than the first foam layer 516, sothat a ring of adhesive 514 remains exposed, and the adhesive 514 is anFDA-approved adhesive that can be placed in direct contact with thepatient's skin and that will maintain reasonable adherence to the skineven when wet, such as any of a variety of FDA-approved siliconeadhesives known in the art and used on colostomy pouches.

[0034] One or more additional viscoelastic foam layers 518 can besecured to the first layer 516 by any known method, such as by usingadhesives or hot-melt glues. Although not required for the pad 510 tofunction as intended, in the embodiment shown, all the layers 516, 518of viscoelastic foam have approximately similar lengths L₅ and widthsW₅, although the thicknesses T₅ may vary.

[0035] In one embodiment, the hydrophilic polyether polyurethane foamlayer 512 is a ¼″ thick foam produced by Lendell Manufacturing Inc., St.Charles, Mich., and sold under the product label Medisponge. This foamis designed to absorb wound exudates, inhibit protein binding, andfacilitate wound healing. A thin layer of silicone adhesive 514 is usedto secure the absorbent foam 512 to a ½″ thick pad of SRF EP-3viscoelastic foam 516 produced by Lendell Manufacturing Inc. A secondlayer of viscoelastic foam 518—½″ thick layer of SRF CB-11 foam producedby Lendell Manufacturing Inc.—is secured to the first foam layer 516with a hot-melt adhesive.

[0036] The pressure relief pad 510 is designed to be positioned on apatient directly over an open wound, or over an area that has a highprobability of forming an open wound, with the hydrophilic polyetherpolyurethane foam layer 512 being placed in direct contact with the skinand wound, the exposed section of adhesive 514 being in direct contactwith the skin, and the viscoelastic layers 516, 518 facing away from thepatient. When positioned on the patient, the hydrophilic foam layer 512absorbs any exudates from the wound, the adhesive 514 holds the pad 510in position, and the viscoelastic layers 516, 518 provide cushioning forthe wound and high pressure area. Further, the viscoelastic layers 516,518 and any air which may be trapped between the layers 516, 518 canhelp the rate of recovery for the wound area and can minimize theprobability of reoccurrence of a similar wound by causing the pressureto be redistributed over a larger region as the viscoelastic layers 516,518 compact and recover under pressure from the patient. Thus, by usinga variety of combinations of viscoelastic foams, pressure relief padscan be produced that respond to a wide range of applied pressures.

[0037] As shown in FIGS. 14 and 15, a hydrophilic polyether polyurethanefoam layer 612 may be included in the contoured pad 10, or in any of theother contoured pads 110, 210, 310, 410. The hydrophilic foam layer 612can be fitted into the cup 26 of the wound covering pad shell 20 toabsorb any exudate from the patient's wound. Alternative, the cup 26 maybe filled with a hydrophilic gel which can further relieve pressure onthe wound area.

[0038] From a reading of the above, one with ordinary skill in the artshould be able to devise variations to the inventive features. Forexample, the ribs may have different shapes or configurations, and theclosure detail, such as the finger grips on the outer shell, may vary indesign. These and other variations are believed to fall within thespirit and scope of the attached claims.

1. A wound covering pressure relieving pad comprising: a. a shell,having a base with a periphery and a side projecting upwardly from saidbase adjacent to said periphery, wherein said base and said side form acup contoured to accommodate a specified body part; b. a platform,fixedly attached to said shell base such that said platform opposes saidshell, said platform being composed of a resilient foam material; and c.a means for reversibly securing said shell to said body part:
 2. The padof claim 1 wherein said shell is composed of a resilient foam.
 3. Thepad of claim 2 wherein said shell is composed of a visco elastic foammaterial.
 4. The pad of claim 1 wherein said shell is composed of aplurality of layers of a resilient material, said layers being fixedlyattached one to another, and each layer including an aperture sized andpositioned to form the cup.
 5. The pad of claim 4 wherein said shelllayers are composed of a viscoelastic foam material.
 6. The pad of claim4 further including at least one non-continuous layer secured to saidshell layers so as to form a rim on said cup, wherein said rim includesa recessed area.
 7. The pad of claim 1 wherein said platform is composedof a viscoelastic foam material.
 8. The pad of claim 1 wherein saidplatform is composed of a plurality of layers of a resilient material.9. The pad of claim 8 wherein said platform layers are composed of aviscoelastic foam material.
 10. The pad of claim 1 wherein said securingmeans is at least one strap, positioned between said shell and saidplatform.
 11. The pad of claim 10 wherein said strap is made of gauze,linen, low-denier cotton, low-denier polyester, or a combinationthereof.
 12. The pad of claim 1 further including a exudate absorbingmaterial fixedly secured within said cup.
 13. The pad of claim 12wherein said exudate absorbing material is a hydrophilic polyetherpolyurethane foam.
 14. A wound covering pressure relieving padcomprising: a. a first layer of resilient material having an aperture ofsufficient size to circumscribe a wound; b. a second layer of resilientmaterial fixedly attached to said first layer such that a cavity isformed; and c. a means for reversibly securing said first layer to apatient's skin.
 15. The pad of claim 14 wherein said first layer iscomposed of a resilient foam.
 16. The pad of claim 15 wherein said firstlayer is composed of a viscoelastic foam material.
 17. The pad of claim14 wherein said second layer is composed of a resilient material. 18.The pad of claim 17 wherein said second layer is composed of aviscoelastic foam material.
 19. The pad of claim 14 wherein saidsecuring means is at least one strap, positioned between said firstlayer and said second layer.
 20. The pad of claim 19 wherein said strapis made of gauze, linen, low-denier cotton, low-denier polyester, or acombination thereof.
 21. The pad of claim 14 further including a exudateabsorbing material fixedly secured within said cup.
 22. The pad of claim21 wherein said exudate absorbing material is a hydrophilic polyetherpolyurethane foam.
 23. The pad of claim 14 further including at leastone cavity layer having an aperture of sufficient size to circumscribesaid wound, said cavity layer being fixedly attached to said first layeropposite said second layer.
 24. The pad of claim 14 further including atleast one base layer fixedly attached to said second layer oppositessaid first layer.
 25. A wound covering pressure relieving padcomprising: a. a layer of resilient material, having a first face and asecond face; b. a layer of adhesive, covering the first face of saidresilient material; c. a layer of exudate absorbing material positionedon said adhesive layer; and d. a means for reversibly securing saidabsorbing material adjacent to a patient's skin.
 26. The pad of claim 25wherein said resilient material is a viscoelastic material.
 27. The padof claim 25 wherein said adhesive is a silicone based material.
 28. Thepad of claim 25 wherein said exudate absorbing material is a hydrophilicpolyether polyurethane foam.
 29. The pad of claim 25 wherein saidsecuring means is at least one strap, positioned between said resilientmaterial layer and said absorbing material layer.
 30. The pad of claim25 wherein said absorbing material layer is smaller than said resilientmaterial layer and said absorbing material layer is positioned on saidresilient material layer so as to leave a band of adhesive exposed atthe outer edge of said resilient material layer, and wherein the meansfor reversibly securing said absorbing material adjacent to a patient'sskin is the band of adhesive.